Wheeler is a great pitching prospect, but he’s not big league ready as a starter, just as Matt Harvey was not big league ready in April, 2012. He must improve his command, and become more comfortable throwing his off-speed stuff early in counts and for strikes rather than just chase pitches late in counts. Wheeler’s 1.9 K/BB ratio (19 K/10 BB) in 21 innings in AAA indicate clearly that he must continue to refine his location. Wheeler threw 116 innings last year and is now sitting at 137 innings for the year. With two more starts in AAA, he should come near 150 innings. At that point, right after Labor Day, the Mets could call him up to the big leagues, or shut him down. He will need to be added to the team’s 40-man roster over the winter to protect him from the Rule 5 draft.
To read more from Toby on Wheeler, including his thoughts on Zack's most recent start, check out this post on Mets Minor League Blog.